Newcastle boss Alan Pardew has been dealt a major blow as summer signing Siem de Jong could be sidelined for months by injury.

The Magpies confirmed on Friday that the 25-year-old Holland international has damaged his right thigh in training and faces a lengthy recovery period.

A spokesman said: "Siem de Jong sustained an injury to his right thigh in training earlier this week and is to be assessed further at the start of next week.

"Initial indications are that he is likely to be out for a number of months."

The timing could hardly have been worse for Pardew at the end of a week during which the transfer window closed without another striker being recruited, while at the same time Hatem Ben Arfa was controversially allowed to join Hull on loan.

De Jong was seen as the man to link midfield with attack, playing behind loan frontman Emmanuel Riviere, contributing both service and goals to a team which has lost the firepower of Loic Remy and the invention of Yohan Cabaye since the turn of the year.

Newcastle have stuttered through the opening weeks of the new season, failing to score in either of their opening two Barclays Premier League games and being denied victory at the death in their third, a disappointing 3-3 home draw with Crystal Palace.

Pardew will now have to hope largely untried new recruits Ayoze Perez and Facundo Ferreyra, as well as midfielder Remy Cabella, can plug the gap.

De Jong's misfortune should perhaps not come as too much of a surprise as he missed much of last season at Ajax through injury and sat out a significant proportion of the Magpies' pre-season campaign with a foot problem.

His absence will do little to quell growing frustration among large sections of the club's support which reached new heights on Monday when the striker and defender they hoped might arrive failed to materialise and instead, Ben Arfa and central defender Mapou Yanga-Mbiwa departed on loan.

Ben Arfa in particular has become a cause celebre for Pardew's critics after being frozen out of the first-team squad.